A couple times now I've edited my .procmailrc file, unwittingly screwed something up, and only discovered my mistake after a day or two goes by with not a peep out of otherwise high traffic lists.
But what happens to a message when procmail gets confused by a broken recipe? Nothing shows up in in /var/spool/mail. And my .forward file goes a little something like this: "|IFS='' && exec /usr/bin/procmail || exit 75 #username" The only explanation I can think of is that procmail is hiding the messages in the same place the clothes dryer likes to hide some of my socks from time to time ;)